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Physical Sciences and Mathematics

University of Massachusetts Amherst

2009

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Asymptotic Stability Of Small Bound States In The Discrete Nonlinear Schrodinger Equation, Pg Kevrekidis, De Pelinovsky, A Stefanov Dec 2009

Asymptotic Stability Of Small Bound States In The Discrete Nonlinear Schrodinger Equation, Pg Kevrekidis, De Pelinovsky, A Stefanov

Panos Kevrekidis

Asymptotic stability of small bound states in one dimension is proved in the framework of a discrete nonlinear Schrödinger equation with septic and higher power-law nonlinearities and an external potential supporting a simple isolated eigenvalue. The analysis relies on the dispersive decay estimates from Pelinovsky and Stefanov [J. Math. Phys., 49 (2008), 113501] and the arguments of Mizumachi [J. Math. Kyoto Univ., 48 (2008), pp. 471–497] for a continuous nonlinear Schrödinger equation in one dimension. Numerical simulations suggest that the actual decay rate of perturbations near the asymptotically stable bound states is higher than the one used in the analysis.

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Short-Wavelength Technology And The Potential For Distributed Networks Of Small Radar Systems, David Mclaughlin, David Pepyne, Brenda Philips, James Kurose, Michael Zink, David Westbrook, Eric Lyons, Eric Knapp, Anthony Hopf, Alfred Defonzo, Robert Contreras, Theodore Djaferis, Edin Insanic, Stephen Frasier, V. Chandrasekar, Francesc Junyent, Nitin Bharadwaj, Yanting Wang, Yuxiang Liu, Brenda Dolan, Kelvin Droegemeier, Jerald Brotzge, Ming Xue, Kevin Kloesel, Keith Brewster, Frederick Carr, Sandra Cruz-Pol, Kurt Hondl, Pavlos Kollias Dec 2009

Short-Wavelength Technology And The Potential For Distributed Networks Of Small Radar Systems, David Mclaughlin, David Pepyne, Brenda Philips, James Kurose, Michael Zink, David Westbrook, Eric Lyons, Eric Knapp, Anthony Hopf, Alfred Defonzo, Robert Contreras, Theodore Djaferis, Edin Insanic, Stephen Frasier, V. Chandrasekar, Francesc Junyent, Nitin Bharadwaj, Yanting Wang, Yuxiang Liu, Brenda Dolan, Kelvin Droegemeier, Jerald Brotzge, Ming Xue, Kevin Kloesel, Keith Brewster, Frederick Carr, Sandra Cruz-Pol, Kurt Hondl, Pavlos Kollias

James Kurose

Dense networks of short-range radars capable of mapping storms and detecting atmospheric hazards are described. Composed of small X-band (9.4 GHz) radars spaced tens of kilometers apart, these networks defeat the Earth curvature blockage that limits today's long-range weather radars and enables observing capabilities fundamentally beyond the operational state-of-the-art radars. These capabilities include multiple Doppler observations for mapping horizontal wind vectors, subkilometer spatial resolution, and rapid-update (tens of seconds) observations extending from the boundary layer up to the tops of storms. The small physical size and low-power design of these radars permits the consideration of commercial electronic manufacturing approaches and …

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Type-1.5 Superconducting State From An Intrinsic Proximity Effect In Two-Band Superconductors, Egor Babaev, Johan Carlstrom, Martin Speight Oct 2009

Type-1.5 Superconducting State From An Intrinsic Proximity Effect In Two-Band Superconductors, Egor Babaev, Johan Carlstrom, Martin Speight

Egor Babaev

We show that in multiband superconductors even small interband proximity effect can lead to a qualitative change in the interaction potential between superconducting vortices by producing long-range intervortex attraction. This type of vortex interaction results in unusual response to low magnetic fields leading to phase separation into domains of a two-component Meissner states and vortex droplets.

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Modulation Of Enzyme-Substrate Selectivity Using Tetraethylene Glycol Functionalized Gold Nanoparticles, Bj Jordan, R Hong, G Han, S Rana, Vm Rotello Oct 2009

Modulation Of Enzyme-Substrate Selectivity Using Tetraethylene Glycol Functionalized Gold Nanoparticles, Bj Jordan, R Hong, G Han, S Rana, Vm Rotello

Vincent Rotello

Tetraethylene glycol (TEG) functionalized gold nanoparticles with 2 nm core diameters (AuTEG) enhance α-chymotrypsin (ChT) enzyme activity in a substrate-selective fashion. We explored the hydrolysis of four different substrates and observed a marked increase in activity with the most hydrophobic substrate N-succinyl-alanine-alanine-proline-phenylalanine- p-nitroanilide (TP), while the other substrates remain virtually unaffected by the AuTEG 'crowding effect' in solution. The enhancement in catalysis is indicated by an increase in Kcat/Km as obtained from Lineweaver–Burk analysis and we hypothesize it to arise from a macromolecular crowding effect analogous to that observed with high molecular weight poly(ethylene glycol) (PEG) polymers.

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Synergistic Effects Of Mutations And Nanoparticle Templating In The Self-Assembly Of Cowpea Chlorotic Mottle Virus Capsids, Se Aniagyei, Cj Kennedy, B Stein, Da Willits, T Douglas, Mj Young, M De, Vm Rotello, D Srisathiyanarayanan, Cc Kao, B Dragnea Sep 2009

Synergistic Effects Of Mutations And Nanoparticle Templating In The Self-Assembly Of Cowpea Chlorotic Mottle Virus Capsids, Se Aniagyei, Cj Kennedy, B Stein, Da Willits, T Douglas, Mj Young, M De, Vm Rotello, D Srisathiyanarayanan, Cc Kao, B Dragnea

Vincent Rotello

A study of the in vitro nanoparticle-templated assembly of a mutant of cowpea chlorotic mottle virus lacking most of the N-terminal domain (residues 4-37), NDelta34, is presented. Mutant empty proteins assemble into empty capsids with a much broader distribution of sizes than the wild-type virus. This increased flexibility in the assembly outcomes is known to be detrimental for the assembly process in the presence of molecular polyanions. However, when rigid polyanionic cores are used, such as nanoparticles, the assembly process is restored and virus-like particles form. Moreover, the breadth of the nanoparticle-templated capsid size distribution becomes comparable with the wild-type …

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Multimodal Drug Delivery Using Gold Nanoparticles, Ck Kim, P Ghosh, Vm Rotello Sep 2009

Multimodal Drug Delivery Using Gold Nanoparticles, Ck Kim, P Ghosh, Vm Rotello

Vincent Rotello

Gold nanoparticles (AuNPs) are promising nanocarriers for therapeutics due to their facile synthesis, ease of functionalization, biocompatibility, and inherent non-toxicity. The unique chemical and physical properties of AuNP monolayers provide versatility in delivery method and tunability of surface properties. Here, we discuss several strategies to utilize the properties of AuNPs for drug delivery.

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A Switch In Retrograde Signaling From Survival To Stress In Rapid Onset Neurodegeneration, Jennifer Ross, Erika L.F Holzbaur, Robert G. Kalb, Karen E. Wallace, Ram Dixit, Goo-Bo Jeong, Eran Perlson Aug 2009

A Switch In Retrograde Signaling From Survival To Stress In Rapid Onset Neurodegeneration, Jennifer Ross, Erika L.F Holzbaur, Robert G. Kalb, Karen E. Wallace, Ram Dixit, Goo-Bo Jeong, Eran Perlson

Jennifer Ross

Retrograde axonal transport of cellular signals driven by dynein is vital for neuronal survival. Mouse models with defects in the retrograde transport machinery, including the Loa mouse (point mutation in dynein) and the Tgdynamitin mouse (overexpression of dynamitin), exhibit mild neurodegenerative disease. Transport defects have also been observed in more rapidly progressive neurodegeneration, such as that observed in the SOD1G93A transgenic mouse model for familial amyotrophic lateral sclerosis (ALS). Here, we test the hypothesis that alterations in retrograde signaling lead to neurodegeneration. In vivo, in vitro, and live-cell imaging motility assays show misregulation of transport and inhibition of retrograde signaling …

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Non-Isotropy Of The Cmb Power Spectrum In Single Field Inflation, John Donoghue, Koushik Dutta, Andreas Ross Jul 2009

Non-Isotropy Of The Cmb Power Spectrum In Single Field Inflation, John Donoghue, Koushik Dutta, Andreas Ross

John Donoghue

Contaldi et al. [1] have suggested that an initial period of kinetic energy domination in single field inflation may explain the lack of CMB power at large angular scales. We note that in this situation it is natural that there also be a spatial gradient in the initial value of the inflaton field, and that this can provide a spatial asymmetry in the observed CMB power spectrum, manifest at low multipoles. We investigate the nature of this asymmetry and comment on its relation to possible anomalies at low multipoles.

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Formation And Size Tuning Of Colloidal Microcapsules Via Host-Guest Molecular Recognition At The Liquid-Liquid Interface, D Patra, F Ozdemir, Or Miranda, B Samanta, A Sanyal, Vm Rotello Jun 2009

Formation And Size Tuning Of Colloidal Microcapsules Via Host-Guest Molecular Recognition At The Liquid-Liquid Interface, D Patra, F Ozdemir, Or Miranda, B Samanta, A Sanyal, Vm Rotello

Vincent Rotello

Stimuli-responsive colloidal microcapsules have been fabricated at the oil−water interface using molecular recognition between functionalized gold nanoparticles. Water-soluble β-cyclodextrin-capped gold nanoparticles and organo-soluble adamantyl-functionalized gold nanoparticles are self-assembled at the water−toluene interface via specific host−guest molecular interactions to provide robust microcapsules. Multivalent interactions of complementary ligands on the nanoparticle surface provide stability to these capsules. Unlike covalently cross-linked microcapsules, the reversible nature of these bridging interactions can be used to manipulate the size of these capsules via introduction of competing adamantane containing amphiphilic guest molecules. Partial disruption of interfacial cross-linking allows microcapsules to coalesce with each other to form larger …

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Gauge Federation As An Alternative To Unification, John Donoghue, Preema Pais May 2009

Gauge Federation As An Alternative To Unification, John Donoghue, Preema Pais

John Donoghue

We motivate and explore the possibility that extra SU(N) gauge groups may exist independently of the Standard Model groups, yet not be subgroups of some grand unified group. We study the running of the coupling constants as a potential evidence for a common origin of all the gauge theories. Several different example are displayed. Some of the multiple options involve physics at the TeV scale.

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Minimizing Detection Probability Routing In Ad Hoc Networks Using Directional Antennas, Xiaofeng Lu, Donald Towsley, Pietro Lio, Fletcher Wicker, Zhang Xiong May 2009

Minimizing Detection Probability Routing In Ad Hoc Networks Using Directional Antennas, Xiaofeng Lu, Donald Towsley, Pietro Lio, Fletcher Wicker, Zhang Xiong

Donald F. Towsley

In a hostile environment, it is important for a transmitter to make its wireless transmission invisible to adversaries because an adversary can detect the transmitter if the received power at its antennas is strong enough. This paper defines a detection probability model to compute the level of a transmitter being detected by a detection system at arbitrary location around the transmitter. Our study proves that the probability of detecting a directional antenna is much lower than that of detecting an omnidirectional antenna if both the directional and omnidirectional antennas provide the same Effective Isotropic Radiated Power (EIRP) in the direction …

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Observation Of Double-Charge Discrete Vortex Solitons In Hexagonal Photonic Lattices, B Terhalle, T Richter, Kjh Law, D Gories, P Rose, Tj Alexander, Pg Kevrekidis, As Desyatnikov, W Krolikowski, F Kaiser, C Denz, Ys Kivshar Apr 2009

Observation Of Double-Charge Discrete Vortex Solitons In Hexagonal Photonic Lattices, B Terhalle, T Richter, Kjh Law, D Gories, P Rose, Tj Alexander, Pg Kevrekidis, As Desyatnikov, W Krolikowski, F Kaiser, C Denz, Ys Kivshar

Panos Kevrekidis

We report on the experimental observation of stable double-charge discrete vortex solitons generated in hexagonal photonic lattices created optically in self-focusing nonlinear media and show that single-charge vortex solitons are unstable in analogous conditions. Subsequently, we study, both theoretically and experimentally, the existence and stability of spatial vortex solitons in two-dimensional hexagonal photonic lattices. We demonstrate that the stability of the double-charge vortices is a consequence of the intersite power exchange in the vortex soliton, and we provide a simple stability criterion on the basis of the analysis of the corresponding discrete nonlinear model. We extend our analysis to the …

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Photoregulated Release Of Caged Anticancer Drugs From Gold Nanoparticles, Ss Agasti, A Chompoosor, Cc You, P Ghosh, Ck Kim, Vm Rotello Apr 2009

Photoregulated Release Of Caged Anticancer Drugs From Gold Nanoparticles, Ss Agasti, A Chompoosor, Cc You, P Ghosh, Ck Kim, Vm Rotello

Vincent Rotello

An anticancer drug (5-fluorouracil) was conjugated to the surface of gold nanoparticles through a photocleavable o-nitrobenzyl linkage. In this system, the particle serves as both cage and carrier for the therapeutic, providing a nontoxic conjugate that effectively releases the payload upon long wavelength UV irradiation.

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Formation Of Ordered Cellular Structures In Suspension Via Label-Free Negative Magnetophoresis, Md Krebs, Rm Erb, Bb Yellen, B Samanta, A Bajaj, Vm Rotello, E Alsberg Mar 2009

Formation Of Ordered Cellular Structures In Suspension Via Label-Free Negative Magnetophoresis, Md Krebs, Rm Erb, Bb Yellen, B Samanta, A Bajaj, Vm Rotello, E Alsberg

Vincent Rotello

The creation of ordered cellular structures is important for tissue engineering research. Here, we present a novel strategy for the assembly of cells into linear arrangements by negative magnetophoresis using inert, cytocompatible magnetic nanoparticles. In this approach, magnetic nanoparticles dictate the cellular assembly without relying on cell binding or uptake. The linear cell structures are stable and can be further cultured without the magnetic field or nanoparticles, making this an attractive tool for tissue engineering.

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Size And Geometry Dependent Protein-Nanoparticle Self-Assembly, M De, Or Miranda, S Rana, Vm Rotello Mar 2009

Size And Geometry Dependent Protein-Nanoparticle Self-Assembly, M De, Or Miranda, S Rana, Vm Rotello

Vincent Rotello

Fundamentally different assembly motifs are observed when proteins of different sizes are complexed with monolayer-protected nanoparticles.

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Transitional Probabilities For The Four-State Random Walk On A Lattice In The Presence Of Partially Reflecting Boundaries, Ramakrishna Janaswamy Mar 2009

Transitional Probabilities For The Four-State Random Walk On A Lattice In The Presence Of Partially Reflecting Boundaries, Ramakrishna Janaswamy

Ramakrishna Janaswamy

The four-state random walk (4RW) model, wherein the particle is endowed with two states of spin and two states of directional motion in each space coordinate, permits a stochastic solution of the Schrödinger equation (or the equivalent parabolic equation) without resorting to the usual analytical continuation in complex space of the particle trajectories. Analytical expressions are derived here for the various transitional probabilities in a 4RW by employing generating functions and eigenfunction expansions when the particle moves on a 1+1 space-time lattice with two-point boundary conditions. The most general case of dissimilar boundaries with partially reflecting boundary conditions is treated …

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Intermolecular Electron-Transfer Catalyzed On Nanoparticle Surfaces, Am Carver, M De, H Bayraktar, S Rana, Vm Rotello, Mj Knapp Feb 2009

Intermolecular Electron-Transfer Catalyzed On Nanoparticle Surfaces, Am Carver, M De, H Bayraktar, S Rana, Vm Rotello, Mj Knapp

Vincent Rotello

Surface-functionalized nanoparticles enhance the rate of electron transfer (ET) between Cyt c(Fe2+) and Co(phen)33+ by a factor of 105 through simultaneous electrostatic binding of an ET donor and acceptor.

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Stable Higher-Charge Discrete Vortices In Hexagonal Optical Lattices, Kjh Law, Pg Kevrekidis, Tj Alexander, W Krolikowski, Ys Kivshar Feb 2009

Stable Higher-Charge Discrete Vortices In Hexagonal Optical Lattices, Kjh Law, Pg Kevrekidis, Tj Alexander, W Krolikowski, Ys Kivshar

Panos Kevrekidis

We show that double-charge discrete optical vortices may be completely stable in hexagonal photonic lattices where single-charge vortices always exhibit dynamical instabilities. Even when unstable the double-charge vortices typically have a much weaker instability than the single-charge vortices, and thus their breakup occurs at longer propagation distances.

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A Comparison Of Turbulent Thermal Convection Between Conditions Of Constant Temperature And Constant Flux, Hans Johnston, Charles R. Doering Feb 2009

A Comparison Of Turbulent Thermal Convection Between Conditions Of Constant Temperature And Constant Flux, Hans Johnston, Charles R. Doering

Hans Johnston

We report the results of high-resolution direct numerical simulations of two-dimensional Rayleigh-Bénard convection for Rayleigh numbers up to Ra=1010 in order to study the influence of temperature boundary conditions on turbulent heat transport. Specifically, we considered the extreme cases of fixed heat flux (where the top and bottom boundaries are poor thermal conductors) and fixed temperature (perfectly conducting boundaries). Both cases display identical heat transport at high Rayleigh numbers fitting a power law Nu≈0.138×Ra0.285 with a scaling exponent indistinguishable from 2/7=0.2857… above Ra=107. The overall flow dynamics for both scenarios, in particular, the time averaged temperature profiles, are also indistinguishable …

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A Comparison Of Turbulent Thermal Convection Between Conditions Of Constant Temperature And Constant Flux, Hans Johnston, Charles R. Doering Feb 2009

A Comparison Of Turbulent Thermal Convection Between Conditions Of Constant Temperature And Constant Flux, Hans Johnston, Charles R. Doering

Hans Johnston

We report the results of high-resolution direct numerical simulations of two-dimensional Rayleigh-Bénard convection for Rayleigh numbers up to Ra=1010 in order to study the influence of temperature boundary conditions on turbulent heat transport. Specifically, we considered the extreme cases of fixed heat flux (where the top and bottom boundaries are poor thermal conductors) and fixed temperature (perfectly conducting boundaries). Both cases display identical heat transport at high Rayleigh numbers fitting a power law Nu≈0.138×Ra0.285 with a scaling exponent indistinguishable from 2/7=0.2857… above Ra=107. The overall flow dynamics for both scenarios, in particular, the time averaged temperature profiles, are also indistinguishable …

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Entrapment Of Hydrophobic Drugs In Nanoparticle Monolayers With Efficient Release Into Cancer Cells, Ck Kim, P Ghosh, C Pagliuca, Zj Zhu, S Menichetti, Vm Rotello Jan 2009

Entrapment Of Hydrophobic Drugs In Nanoparticle Monolayers With Efficient Release Into Cancer Cells, Ck Kim, P Ghosh, C Pagliuca, Zj Zhu, S Menichetti, Vm Rotello

Vincent Rotello

Gold nanoparticles functionalized with water-soluble zwitterionic ligands form kinetically stable complexes with hydrophobic drugs and dyes. These drugs and dyes are efficiently released into cells, as demonstrated through fluorescence microscopy and cytotoxicity assays. Significantly, there is little or no cellular uptake of particle, making these low toxicity particles promising for delivery applications.

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Model Systems For Flavoenzyme Activity: An Investigation Of The Role Functionality Attached To The C(7) Position Of The Flavin Unit Has On Redox And Molecular Recognition Properties, St Caldwell, Lj Farrugia, Sg Hewage, N Kryvokhyzha, Vm Rotello, G Cooke Jan 2009

Model Systems For Flavoenzyme Activity: An Investigation Of The Role Functionality Attached To The C(7) Position Of The Flavin Unit Has On Redox And Molecular Recognition Properties, St Caldwell, Lj Farrugia, Sg Hewage, N Kryvokhyzha, Vm Rotello, G Cooke

Vincent Rotello

We describe the role functionality attached to the C(7) position of a family of flavin derivatives has in tuning their redox and recognition properties and the subsequent exploitation of two of these derivatives as a three-component electrochemically controllable molecular switch.

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Sniffing Out Cancer Using "Chemical Nose" Sensors, V Rotello Jan 2009

Sniffing Out Cancer Using "Chemical Nose" Sensors, V Rotello

Vincent Rotello

No abstract provided.

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Engineered Nanoparticle Surfaces For Improved Mass Spectrometric Analyses, Zj Zhu, Vm Rotello, Rw Vachet Jan 2009

Engineered Nanoparticle Surfaces For Improved Mass Spectrometric Analyses, Zj Zhu, Vm Rotello, Rw Vachet

Vincent Rotello

Engineering of nanoparticle surface functionality provides controlled interactions with biomolecules such as cell membrane lipids, proteins and nucleic acids. Concurrently, this surface chemistry control also opens up new avenues for improving mass spectral analyses. In this Minireview, we highlight some of the emerging work that integrates surface-engineered nanoparticles with mass spectrometry to improve the analysis of a wide variety of chemical and biological systems.

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Beyond Molecular Recognition: Using A Repulsive Field To Tune Interfacial Valency And Binding Specificity Between Adhesive Surfaces, Mm Santore, J Zhang, S Srivastava, Vm Rotello Jan 2009

Beyond Molecular Recognition: Using A Repulsive Field To Tune Interfacial Valency And Binding Specificity Between Adhesive Surfaces, Mm Santore, J Zhang, S Srivastava, Vm Rotello

Vincent Rotello

Surface-bound biomolecular fragments enable “smart” materials to recognize cells and other particles in applications ranging from tissue engineering and medical diagnostics to colloidal and nanoparticle assembly. Such smart surfaces are, however, limited in their design to biomolecular selectivity. This feature article demonstrates, using a completely nonbiological model system, how specificity can be achieved for particle (and cell) binding, employing surface designs where immobilized nanoscale adhesion elements are entirely nonselective. Fundamental principles are illustrated by a model experimental system where 11 nm cationic nanoparticles on a planar negative silica surface interact with flowing negative silica microspheres having 1.0 and 0.5 μm …

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Self-Assembly Of Fluorocarbon-Coated Fept Nanoparticles For Controlling Structure And Wettability Of Surfaces, B Samanta, Y Ofir, D Patra, Vm Rotello Jan 2009

Self-Assembly Of Fluorocarbon-Coated Fept Nanoparticles For Controlling Structure And Wettability Of Surfaces, B Samanta, Y Ofir, D Patra, Vm Rotello

Vincent Rotello

Controlled self-assembly of fluorinated FePt nanoparticles from different solvent mixtures has been used to create superhydrophobic surfaces with varying topology and stickiness towards water. The ability to tune surface stickiness provides a means for fluid handling, as demonstrated by surface-to-surface transfer of water droplets.

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Gold Nanoparticle-Ppe Constructs As Biomolecular Material Mimics: Understanding The Electrostatic And Hydrophobic Interactions, Rl Phillips, Or Miranda, De Mortenson, C Subramani, Vm Rotello, Uhf Bunz Jan 2009

Gold Nanoparticle-Ppe Constructs As Biomolecular Material Mimics: Understanding The Electrostatic And Hydrophobic Interactions, Rl Phillips, Or Miranda, De Mortenson, C Subramani, Vm Rotello, Uhf Bunz

Vincent Rotello

Eleven cationic, monolayer-protected quaternary ammonium-functionalized gold nanoparticles (ANPs) were prepared and investigated for their ability to quench the fluorescence of a poly(p-phenyleneethynylene) (PPE) that features carboxylate groups to enable electrostatic interactions with the ANPs. Depending upon their structures, the ANPs displayed binding constants to the PPE from 8 × 107 to 1010 M−1, with particularly high affinity observed with aromatic functionalized ANPs capable of aromatic stacking. These binding constants were obtained by analyzing the quenching data using a modified Stern–Volmer formalism.

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Beyond Diffusion-Limited Aggregation Kinetics In Microparticle Suspensions, Rm Erb, Md Krebs, E Alsberg, B Samanta, Vm Rotello, Bb Yellen Jan 2009

Beyond Diffusion-Limited Aggregation Kinetics In Microparticle Suspensions, Rm Erb, Md Krebs, E Alsberg, B Samanta, Vm Rotello, Bb Yellen

Vincent Rotello

Aggregation in nondiffusion limited colloidal particle suspensions follows a temporal power-law dependence that is consistent with classical diffusion limited cluster aggregation models; however, the dynamic scaling exponents observed in these systems are not adequately described by diffusion limited cluster aggregation models, which expect these scaling exponents to be constant over all experimental conditions. We show here that the dynamic scaling exponents for 10 μm particles increase with the particle concentration and the particle-particle free energy of interaction. We provide a semiquantitative explanation for the scaling behavior in terms of the long-ranged particle-particle interaction potential.

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Molecular Recognition At The Liquid-Liquid Interface Of Colloidal Microcapsules, D Patra, C Pagliuca, C Subramani, B Samanta, Ss Agasti, N Zainalabdeen, St Caldwell, G Cooke, Vm Rotello Jan 2009

Molecular Recognition At The Liquid-Liquid Interface Of Colloidal Microcapsules, D Patra, C Pagliuca, C Subramani, B Samanta, Ss Agasti, N Zainalabdeen, St Caldwell, G Cooke, Vm Rotello

Vincent Rotello

Dithiocarbamate chemistry is used as a crosslinking tool to fabricate FePt colloidal microcapsules which provide a versatile scaffold for “host–guest” recognition at the liquid–liquid interface.

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A New Era In Extragalactic Background Light Measurements: The Cosmic History Of Accretion, Nucleosynthesis And Reionization, Asantha Cooray, Alexandre Amblard, Charles Beichman, Dominic Benford, Rebecca Bernstein, James J. Bock, Mark Brodwin, Volker Bromm, Renyue Cen, Ranga R. Chary, Mark Devlin, Timothy Dolch, Hervé Dole, Eli Dwek, David Elbaz, Michael Fall, Giovanni Fazio, Henry Ferguson, Steven Furlanetto, Jonathan Gardner, Mauro Giavalisco, Rudy Gilmore, Nickolay Gnedin, Anthony Gonzalez, Zoltan Haiman, Michael Hauser, Jiasheng Huang, Sergei Ipatov, Alexander Kashlinsky, Brian Keating, Thomas Kelsall, Eiichiro Komatsu, Guilaine Lagache, Louis R. Levenson, Avi Loeb, Piero Madau, John C. Mather, Toshio Matsumoto, Shuji Matsuura, Kalevi Mattila, Harvey Moseley, Leonidas Moustakas, S. Peng Oh, Larry Petro, Joel Primack, William Reach, Tom Renbarger, Paul Shapiro, Daniel Stern, Ian Sullivan, Aparna Venkatesan, Michael Werner, Rogier Windhorst, Edward L. Wright, Michael Zemcov Jan 2009

A New Era In Extragalactic Background Light Measurements: The Cosmic History Of Accretion, Nucleosynthesis And Reionization, Asantha Cooray, Alexandre Amblard, Charles Beichman, Dominic Benford, Rebecca Bernstein, James J. Bock, Mark Brodwin, Volker Bromm, Renyue Cen, Ranga R. Chary, Mark Devlin, Timothy Dolch, Hervé Dole, Eli Dwek, David Elbaz, Michael Fall, Giovanni Fazio, Henry Ferguson, Steven Furlanetto, Jonathan Gardner, Mauro Giavalisco, Rudy Gilmore, Nickolay Gnedin, Anthony Gonzalez, Zoltan Haiman, Michael Hauser, Jiasheng Huang, Sergei Ipatov, Alexander Kashlinsky, Brian Keating, Thomas Kelsall, Eiichiro Komatsu, Guilaine Lagache, Louis R. Levenson, Avi Loeb, Piero Madau, John C. Mather, Toshio Matsumoto, Shuji Matsuura, Kalevi Mattila, Harvey Moseley, Leonidas Moustakas, S. Peng Oh, Larry Petro, Joel Primack, William Reach, Tom Renbarger, Paul Shapiro, Daniel Stern, Ian Sullivan, Aparna Venkatesan, Michael Werner, Rogier Windhorst, Edward L. Wright, Michael Zemcov

Mauro Giavalisco

(Brief Summary) What is the total radiative content of the Universe since the epoch of recombination? The extragalactic background light (EBL) spectrum captures the redshifted energy released from the first stellar objects, protogalaxies, and galaxies throughout cosmic history. Yet, we have not determined the brightness of the extragalactic sky from UV/optical to far-infrared wavelengths with sufficient accuracy to establish the radiative content of the Universe to better than an order of magnitude. Among many science topics, an accurate measurement of the EBL spectrum from optical to far-IR wavelengths, will address: What is the total energy released by stellar nucleosynthesis over …

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